Answer:
In the above sentence, 'whenever' is a subordinating conjunction.
Step-by-step explanation:
A conjunction is a part of speech which helps in joining two words, phrases or sentences. A subordinating conjunction is a word which connects an independent clause with a dependent clause. In the above sentence, 'Terry jumps up' is an independent clause while 'anyone rings the doorbell is a dependent clause. 'Whenever' is the subordinating conjunction which is joining them.